NEW YORK – Product is king again.

After using discounts and promotions to deliver the best holiday sales performance in six years, retailers will need unique merchandise to keep the momentum going.

“It’s got to be all about the product,” said Christine Chen, a Needham & Co. analyst based in San Francisco. Discounts alone are not enough to keep consumers shopping, she said.

Abercrombie & Fitch, Lululemon Athletica and Urban Outfitters are already winning shoppers with quality, fashion and merchandise that can’t be found elsewhere, Chen said. At Abercrombie, teenagers trading up to dresses from graphic T-shirts helped drive December same-store sales to almost five times the industry average. Coach Tuesday reported a 26 percent increase in second-quarter profit after introducing new bags more frequently during the holidays.

Exclusive merchandise may help decide winners in retail in 2011. Even as the economy improves, existing stores likely will post sales growth of 3.4 percent, about the same as they were in fiscal 2010, which ends Jan. 29, according to the International Council of Shopping Centers in New York.

“We are going to see increased retail prices and fewer promotions, and that means the consumer is not going to be motivated to buy,” said Marshal Cohen, chief industry analyst at market researcher NPD Group Inc.

Retailers may be hurting themselves by remaining timid in the wake of the recession and not renewing investments in new products, Cohen said. That may lead to a dearth of the innovation needed to persuade shoppers to buy.

Americans also are savvier shoppers now, says Richard Hastings, a consumer strategist for Global Hunter Securities.

Price trumped product quality during the slump and for much of its aftermath, says Hastings, who is based in Charlotte, N.C. No longer.

“Customers are looking for quality and value,” said Claudio Del Vecchio, chief executive officer of Retail Brand Alliance, the closely held owner of Brooks Brothers, the men’s clothing chain. “They are willing to make the investment in something of better quality if they know it is timeless and authentic, which will endure rather than impulsively buying several trendy items.”

Strong sellers at Brooks Brothers include $398 cashmere sweaters and the two-button Fitzgerald suit, which costs about $1,100, Del Vecchio said.

To woo customers with a fresher variety of merchandise during the past quarter, Coach Chief Executive Officer Lew Frankfort staggered handbag updates instead of debuting the bulk of them in October. The purse maker also introduced a line of tote bags in mid-December called Alexandria.

Coach shares have advanced about 56 percent over the past 12 months.